1. Field of the Invention
The invention is related to semiconductor processing, and more particularly to a plasma generation apparatus and process for processing a semiconductor substrate with remotely generated plasma.
2. Description of the Related Art
Various systems and methods are well known for processing semiconductor substrates. For example, some processes include depositing thin films and/or dielectric layers on the semiconductor substrates. A typical deposition technique uses plasma generated in a processing chamber during a CVD process (hereinafter xe2x80x9cplasma CVDxe2x80x9d or xe2x80x9cPECVDxe2x80x9d) to form a thin film layer.
FIG. 1 is a simplified schematic view illustrating the fundamental components of a conventional self-biasing type plasma CVD device 100 used to process the semiconductor substrate. Plasma CVD device 100 uses a radio-frequency (RF) generator (13.56 MHz), to create a glow discharge region between a bottom electrode 102 and a top electrode 104. The RF generator activates a reaction in a gaseous mixture to deposit a film on substrate 106 located on bottom electrode 102. Bottom electrode 102 and top electrode 104 are arranged opposite to one another in a reaction chamber (not shown). Bottom electrode 102 is connected to an external DC electrical power source 108. Top electrode 104 is connected to a radio-frequency generator 110. A grooved mesh electrode 112 is located between bottom electrode 102 and top electrode 104 and a DC bias current is applied between mesh electrode 112 and bottom electrode 102. In this device, ions and radicals incident on the substrate are controlled by applying a direct current flow without grounding bottom electrode 102 supporting substrate 106.
Unfortunately, since the surface of substrate 106 on which the film is deposited is located near the plasma generation region, high-energy particles generated by plasma discharge frequently bombard the substrate surface. This may cause the thin film to deteriorate, become damaged or to be deposited abnormally by the impact of particles having excessive energy.
The present invention provides an apparatus and associated methods for processing a semiconductor substrate using components and particles of a plasma discharge formed in a remote section of a processing chamber. The present invention reduces the amount of high-energy particles, generated by the plasma discharge, which can bombard the substrate surface. The present invention includes a processing chamber having a processing section and a plasma generation section. A plasma field is generated in the plasma generation section, such that the plasma field is generated outside or away from a substrate disposed in the processing section. Components and particles from the plasma field can diffuse and/or drift from the plasma generation section through a passageway to the processing section to interact with the substrate. Advantageously, the processing chamber may include a plurality of plasma generation sections for generating additional plasma fields. In each instance, the additional plasma fields are generated remotely from the processing section.
In one aspect of the invention, an apparatus is provided for processing a substrate. The apparatus includes a processing chamber and a plasma generation chamber. A plasma is generated in the plasma generation chamber. The processing chamber and the plasma generation chamber include a passageway between them to allow a plasma field component to move from the plasma generation chamber to the processing chamber.
In another aspect of the invention, a plasma generation process is provided for processing a semiconductor substrate. The process includes providing a chamber, which has a first plasma generation section and a processing section. The process also includes generating a first plasma field in the first plasma generation section and moving components of the first plasma field from the first plasma generation section to the processing section. The components interact with a substrate disposed in the processing section.
In another aspect of the present invention, a process is provided for processing a substrate including generating a plasma in a first section of a substrate processing chamber; and moving components proximate to a substrate disposed in a second section of the substrate processing chamber. The first section being remote from the second section.
These and other features and advantages of the present invention will be more readily apparent from the detailed description of the embodiments set forth below taken in conjunction with the accompanying drawings.